Conditional lysozyme sensitive spore mutants are being studied. The defect is expressed at the time of spore coat formation and does not appear to improve the major coat structural proteins. Other mutants isolated for defective intracellular protease also produce lysozyme sensitive spores. These spores germinate poorly and do not readily release from the mother cell. The spores are deficient in coat protein but coat antigen is found in cell extracts. Various aspects of spore formation regulation being studied are (1) the role of glutamine synthetase via isolation and characterization of B. subtilis mutants, (2) synthesis of spore coat protein in stage zero B. subtilis mutants and, (3) in vitro synthesis of spore coat polypeptides. BIBLIOGRAPHIC REFERENCES: Aronson, A. I. and P.C. Fitz James (1975). Properties Bacillus cereus spore coat mutants. J. Bacteriol. 123,354-365. Aronson, A. I. and P.C. Fitz James (1976). Structure and morphogenesis of the bacterial spore coat. Bacteriol. Rev.